Apparatus for obtaining data for gunnery purposes



June 5, 1928. 1,672,026

P. w. GRAY APPARATUS FOR'QBTAINING DATA FOR GUNNERY PURPOSES Filed June 15, 1921 nnnnnnnnnunnnnnnn with;

PERCY WILLIS GRAY, OF WESTMINSTER, ENGLAND, ASSIGNOR TO VICKERS LIMITED, OF WESTMINSTER, ENGLAND.

APPARATUS FOR OBTAINING DATA FOR GUNNERY PURPOSES.

Application filed. June 15, 1921, Serial No. 477,740, and in Great Britain December 15, 1919.

This invention relates to apparatus for obtaining data for gunnery purposes the said apparatus being such that the rate of displacement of a member forming part thereof to an extent proportional to the deflection rate of a target in relation to the gun position (either the target or the gun position or both being in motion) causes displacement in unit time of another member to an extent which is proportional to the rate of change of bearing between the target and the gun position. Deflection rate is a linear measurement which may be represented by the expression 5 R where S is the rate of change of bearing and R is the range of the target and in order to obtain the said displacement equal to 2 my improved apparatus comprises a system of linkage which when adjusted in conformity with S R and with R, will operate to divide the former quantity by R and to displace a member by an amount proportional to the quotient S i. e. proportional to the rate of change of bearing, the said apparatus being thus distinguished from a known apparatus in which the resultant s is obtained by multiplying a displacement corresponding to S- R by a displacement corresponding to the reciprocal of R. The displacement of the last mentioned member may serve to indicate by means of a suitable scale the actual rate of change of bearing thus obtained or it may be employed (with or without such indication) for setting the variable speed mechanism of a bearing clock in accordance with the rate of change of bearing.

In order that the said invention may be clearly understood and readily carried into effect the same will be more fully described with reference to the accompanying drawings in which Figures 1 and 2 are views showing diagrammatically two forms of apparatus in accordance with the invention.

In these figures A is an arm pivoted-at a to a fixed part and formed with a slot a to receive a pin or projection 6* on a slider B mounted on a bar C (herein termed the range slide) which is capable of being moved bodily in a direction transverse to its length in accordance with the deflection S B. This movement may be effected by hand in accordance with the known or ascertained deflection or it may be effected automatically from any known or desired arrangement of pivoted bars adjustable as regards length and direction according to the speed and course of own ship (assuming the apparatus to be mounted on a ship) and in accordance with the speed and course of enemy ship or target. In the examples shown this arrangement of pivoted bars is intended to be used, D representing a pin on one of these bars which pin occupies a position depending upon the speeds and courses and engages in a slot (Z in a part D rigid with the range slide C. The slider B is adjustable along the range slide C in accordance with the range R (for example by a screw B operated by a head 6) the zero range position of the slider (which in practice it never occupies) being that in which the axis of the pin or projection I) and the axis of the pivot a are situated in a plane disposed at right angles to the range slide C and the zero deflection position of the said slide being that in which the axis of the pin or projection b and the axis of the pivot a are situated in a plane parallel to the said slide.

It will be noted that the members of my improved device which are moved in accordance with the deflection and the range respectively, have motions which are of the same form. In the embodiment of the invention illustrated in the accompanying drawings, these members both have rectilinear translation motions. Each member moves exactly in proportion to the deflection or range, as the case may be, and they act upon the pivoted member to cause it to rotate through an angle the tangent of which is proportional to the quotient of the deflection divided by the range. The member which is moved by the pivoted member is caused to move exactly in proportion to the tangent of the angle of displacement of the pivoted member, and therefore exactly in proportion to the quotient of the deflection divided by the range.

In the construction shown by Figure 1 an extension A of the arm has a slot a engaging with a pin 6 on a sliding rod E which is constrained by guides E, E, to move in a direction parallel to the path of movement of the range slide C and in Figure 2 the said arm is connected to a suitably shaped cam F which displaces the rod E through a pivoted arm F, the said rod in the latter construction being constrained by the guides E, E to move in a direction at right angles tonnes to that specified in connection with the corresponding rod of Figure 1. This cam instead of being connected to the arm Amight be driven therefrom by gear wheels or segments one of which would be rigidly connected to the said arm A. In any of these cases the said rod E receives in unit tune a displacement proportional to the rate of change of bearing 3 and may as aforesaid serve to indicate the rate of change of bearing or it may operate upon the adjustable member of a variable speed mechanism appertaining to a bearing clock or the bearing clock portion of a combined range and bearing clock; in the drawing G represents the driving disc of the said variable speed mechanism.

The manner in which the rod E operates to move the adjustable member of the variable speed mechanism will be apparent on reference to British Patent No. 16,373 of 1913.

In Figs. 1 and 2, H is a scale graduated to represent rate of change of bearing and J is an index or pointer secured to the rod E so that as the latter moves the index or pointer J indicates the rate of change to bear on the scale H.

In operation the range slide C is moved in accordance with the deflection R in a direction transverse to its length from the aforesaid Zero deflection position, the said range slide (with the aforesaid part D) being constrained to move only in the said direction by the engagement of extensions d, 0 in guides (Z 0 The slider B is also moved from the aforesaid zero range position along the range slide 0 in accordance with the range R, the said slider being constrained by its engagement with the said slide to move only in a direction at right angles to the direction of movement of the slide. It will therefore be apparent that the triangles a, w, 6* and a, 3 6 indicated in Figure 1 will at all times be similar and that if the constant distance a, 3 be taken as unity, the distance e, 51 corresponds to the rate of change of bearing. Similar considerations apply to Figure 2 in which however the cam F and the pivoted lever F take the place of the extension A and the pin and slot connection 6, a with the sliding rod E.

hat I claim and desire to secure by Letters Patent of the United States is 1. An apparatus for obtaining data for gunnery purposes, comprising a member having a translational movement in accordance with the ascertained deflection of a moving target, a pin and block carried by said member and movable at right angles to the translational motion of the first member in accordance with the ascertained range, a pivoted lever provided at one end with a slot engaging the pin and provided at its other end with a second slot, and a third member provided with a pin engaging in said second slot and moved by said lever in accordance with the quotient of the deflection divided by the range.

2. Appa -atus for obtaining data for gunnery purposes, comprising a member moved bodily in proportion to the ascertained deflection of a moving target, a second member associated with the former member and moved bodily in proportion to the ascertained range, a pivoted lever with which part of one of said members slidably engages and a third member which is moved through said lever, by the adjustments of the other two members, in accordance with the quotient of the deflection divided by the range.

3. Apparatus for obtaining data for gunnery purposes, comprising a member moved bodily in proportion to the ascertained deflection of a moving target, a second member associated with the former member and moved bodily in proportion to the ascertained range, a pivoted lever with which part of one of said members slidably engages and a third member which is moved directly by said lever, as a result of the adjustments of the other two members, in accordance with the quotient of the deflection divided by the range.

l. Apparatus for obtaining data for gunnery purposes, comprising a member moved in accordance with the ascertained deflection of a moving target, a second member car ried by the former member and moved in accordance with the ascertained range, a pivoted lever with which part of said second member slidably engages, and a third member slidably connected to said lever and moved thereby in accordance with the quotient of the deflection divided by the range.

5. Apparatus for obtaining data for gunnery purposes, comprising a member moved in accordance with the ascertained deflection of a moving target, a second member moved in accordance with the ascertained range, a third member, and means associated with these three members whereby the adjustments of the first two members serve to move the third member in accordance with the quotient of the deflection divided by the range, the first and second members being constructed and arranged so that their motions are of the same form.

PERCY iVILLIS GRAY. 

